Plant Problem Diagnosis Key / Pests

Pest

Squash bugs and stink bugs

Anasa tristis, Pentatomidae

Flat-backed or shield-shaped sucking bugs. Squash bugs wilt and kill cucurbit leaves; stink bugs leave cloudy spots on tomato and pepper fruit.

Adult squash bug
Adult squash bug Photo: Ilona Loser, CC BY-SA 4.0, via Wikimedia Commons

Signs

What favors it

Debris, weeds and rocks that shelter adults over winter.

Prevention

Often confused with

Sources

Why →

Treatment by crop

Cultural, biological and chemical options in the order to use them, and notes written for each crop.

Identification is free. Treatment is on the Home and Pro plans.

Open in the key See plans

Questions in the key that lead here

  1. Look the plant over, leaf undersides included. Are insects, mites, slugs, eggs, webbing or droppings on it?
    Yes, something living or its traces
  2. What is on the plant?
    Small insects, clustered or flying
  3. Do they fly up when the plant or the soil is disturbed?
    No, they stay put or crawl
  4. What kind of insect?
    Shield-shaped or flat-backed bugs

Not a match? Start the key or describe what you see.

More photos

More from university Extension: search Extension pages on squash bugs and stink bugs, or find a plant diagnostic lab through your state's Extension.

Other pests